Midshaft Humerus Fracture

A 46-year-old man fell from a ladder, injuring his left non-dominant arm. This is an isolated injury and these are his radiographs from the emergency department.

1. What do the radiographs show and how would you manage this patient?

These are plain radiographs of the left humerus. They show a displaced midshaft diaphyseal fracture.

I would take a careful history from the patient and perform a full circumfer- ential examination of the limb, looking for any sign of any open wound, signifi- cant soft tissue injury or ipsilateral fracture. I would perform an examination of the peripheral neurology and vascular status of the limb. Assuming that this is normal, I would place the limb in a hanging U-slab and repeat the radiographs and neurovas- cular assessment. If this was satisfactory I would plan to treat the patient with early functional bracing.

2. What degree of residual displacement or deformity would you consider to be acceptable for non-operative treatment?

I would accept 20 degrees of angulation in the sagittal plane and 30 degrees of angula- tion in the coronal plane.

3. You reassess the neurology and vascular status following application of a plaster cast and you note that the patient has developed altered sensation in the distribu- tion of the radial nerve and a wrist drop. He is complaining of increased pain. How would you proceed?

The patient has developed radial nerve symptoms since the plaster cast was applied. I would remove the plaster cast and reassess the patient. If these symptoms persist then this would be a relative indication for surgical treatment although some sur- geons might treat this more expectantly. Having had normal radial nerve function on presentation and a clear deterioration after manipulation or plaster cast applica- tion, I would plan to explore the nerve and internally fix the fracture on the next available routine trauma list. In the meantime I would ensure that the patient has adequate analgesia and is comfortable either in a collar and cuff or sling.

4. What would be your indications for operative treatment for a midshaft diaphy- seal humerus fracture?

Indications for operative treatment include open fractures, an associated vascular injury, ipsilateral fractures, floating shoulder or elbow, bilateral humerus fractures, polytrauma, failure to obtain and maintain an acceptable closed reduction, patho- logic  fractures,  neurologic  or  brachial  plexus  injuries,  intra-articular  fracture  or extension and unfavourable body habitus, particularly in ladies with large breasts, which might act as a fulcrum at the fracture site.

5. What would you tell the patient about the risks and benefits of operative versus non-operative treatment?

Both treatment options have similar times to union and rates of union. Rates of non- union for midshaft diaphyseal fractures treated with functional bracing are 2–10% but slightly higher for more proximal or long oblique fracture patterns. Compression plating has been found to have a non-union rate around 5–10%. Operative treatment does expose the patient to the risks of iatrogenic nerve or vessel injury and infec- tion but will allow earlier movement of the arm once stabilised. Functional bracing avoids the risks of surgery but may be associated with a longer duration of initial discomfort and pain while the fracture fragments are mobile and there is a higher risk of mal-union, although this may not be of any consequence.

6. How does the Sarmiento functional brace work?

The brace is applied once pain allows and may need to be adjusted once initial swell- ing settles. The brace is made up of overlapping synthetic plastic shells lined with soft foam and fitted to the arm. The shells are contoured to fit the biceps and triceps. They are held with Velcro straps and encircle the arm, applying a compressive force to the soft tissues controlling and splinting the humeral fracture segments. Gravity also assists the realignment of fracture segments. Functional bracing of these mid- shaft fractures allows for some movement of the elbow and shoulder over the course of treatment, reducing unnecessary joint stiffness.